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Affective Disorder
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If you notice periods of depression that seem to accompany seasonal changes during the year, you may suffer from seasonal affective disorder (SAD). This condition is
characterized by recurrent episodes of depression in certain months of the year alternating with periods of normal mood the rest of the year. Usually those affected by SAD become depressed in the fall and winter and feel better during the spring and summer. Atypical cases are also known in which the person becomes depressed Most people with SAD are women whose illness typically begins in their twenties. Milder versions
of SAD have been reported in children and adolescents. Many people with SAD report at least one
close relative with a psychiatric condition, most frequently a severe depressive disorder (55
percent) or alcohol abuse (34 percent).
What are the patterns of SAD?
The usual characteristics of recurrent winter depression include oversleeping,
carbohydrate craving, and weight gain. Other symptoms include the usual
features of depression, especially decreased sexual appetite, lethargy,
hopelessness, suicidal thoughts, lack of interest in normal activities, and social
withdrawal.
Recurrent summer depression is more likely to be characterized by insomnia,
decreased appetite, weight loss, and agitation or anxiety. Patients with SAD in the summer often
have histories of summer trips to the north, where they find relief from depression in cold climates.
Generally, normal air conditioning is not sufficient to relieve depression in these patients during the
summer months.
Symptoms of winter SAD usually begin in October or November and subside in March or April.
Depressions are usually mild to moderate, but they can be severe. Only 6 percent of patients with
SAD seen at the National Institute of Mental Health (NIMH) have required hospitalization, and very
few have been treated with electro-convulsive therapy.
The most common characteristic of people with SAD is their reaction to changes in environmental light. Patients living at different latitudes note that their winter depressions are longer and more profound the farther north they live. Patients with SAD also report that their depression worsens whenever the weather is overcast at any time of the year and/or their indoor lighting is decreased. SAD is often misdiagnosed as hypothyroidism, hypoglycemia, infectious mononucleosis, and other viral infections. How is SAD treated?
Bright, fluorescent (not ordinary) light has been shown to reverse the winter
depressive symptoms of SAD. In a 1986 study, 80 percent of 112 patients improved
significantly with light therapy.
Scientists believe that light therapy works by altering the levels of certain
brain chemicals. Research has shown that antidepressants such as Zoloft
and Prozac may be helpful in treating SAD. Other antidepressants may also
be of value.

How is light therapy used to treat SAD?
Persons with SAD generally begin with 30 to 45 minutes of treatment in
the morning. Light in the evening may cause insomnia. After a week or two, the person with
SAD can experiment with reducing or increasing the daily duration of treatment. The most
common light source is a full spectrum fluorescent light. This fixture provides a reflecting
surface behind the lights and a plastic diffusing screen in front. The light box is placed either
horizontally on a desk or table or vertically on the floor. The intensity of light from this special light
source is equivalent to the amount of light exposure the person would receive from looking out a
window on a sunny spring day.
Side effects of phototherapy are uncommon. Some patients complain of irritability, eye strain,
headaches, or mania. No evidence has been produced of long-term adverse effects, however.
What should I do if I think I have SAD?
Learn as much as you can about SAD. If your symptoms are mild, that is, if they don't interfere too
much with your daily living, you may want to try light therapy as described above or experiment
with adjusting the light in your surroundings with bright lamps.
If your depressive symptoms are severe enough to significantly affect your day-to-day functioning,
consult a mental health professional qualified to treat SAD. He or she can help you find the most
appropriate treatment for you.
What is the effect of sunlight on mood and behavior?
The recent discovery that some forms of depression respond to daily treatment with bright light has
called attention to the popular notion that sunlight is "soul restoring." Many people with seasonal
mood swings seem to gravitate toward sunlight. They also tend to walk around the house turning
on lights to alleviate their symptoms.
Observations of the mood-elevating effects of sunlight may also partly explain the high rates of
suicide and alcohol abuse in places like Seattle and Sweden, where sunshine in winter is
extremely limited. To counteract the depressing effects of short winter days, psychiatrists suggest
taking advantage of sunlight by scheduling time outdoors each day.
Information Provided by:
National Alliance for the Mentally Ill Colonial Place Three, 2107 Wilson Blvd. Ste 300 Arlington, VA 22201-3042

Source: https://www.ctclearinghouse.org/Topics/Customer-Files/SAD_Seasonal_Affective_Disorder_052405.pdf